Labour leader Ed Miliband has said he can win the next election, but that a future Labour government would be different from the last.
In the third of the Today programme New Year leader interviews, Mr Miliband cautioned John Humphrys not to "declare the result of the race when it's only half run".
"I have a very strong inner belief that I will win the race," he said.
The Labour leader said that if Labour took power, they would govern "very differently from the past", as they would not have the money to spend in different economic circumstances.
"That sort of world will not be open to us," he said, insisting that a fairer society could be pursued without spending extra money.
But he refused to accept criticism of the last government that "the problem was Labour over-spending".
He said he would shift money from banking tax-breaks to lower the cost of going to university.
And on welfare, he said anybody who can work should work. "I fundamentally believe in responsibility," he said.
"We have to fundamentally change the way our economy and society works," he said. "That's what I call irresponsible capitalism."
Get in touch with Today via
or text us on 84844.